LayoutShift.lastInputTime

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The lastInputTime read-only property of the LayoutShift interface returns the time of the most recent excluding input or 0 if no excluding input has occurred.

Layout shifts are only bad if the user wasn't expecting them. Many layout shift metrics (like Cumulative Layout Shift (CLS)) exclude shifts that occurred soon after certain user interactions. These interactions are called excluding inputs. Excluding inputs are:

  • Any events which signal a user's active interaction with the document: (mousedown, keydown, and pointerdown)
  • Any events which directly changes the size of the viewport.
  • change events.

The mousemove and pointermove events are not excluding inputs.

Value

A DOMHighResTimeStamp indicating the most recent excluding input time or 0 if no excluding input has occurred.

Examples

Logging last input times

Log excluding input times if excluding input has occurred.

const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    if (entry.lastInputTime) {
      console.log(entry.lastInputTime);
    }
  });
});

observer.observe({ type: "layout-shift", buffered: true });

Specifications

Specification
Layout Instability
# dom-layoutshift-lastinputtime

Browser compatibility

BCD tables only load in the browser

See also